Electric switch



ELECTRIC SWITCH Application February 9, 1955, Serial No. 487,083

7 Claims. (Cl. 200-67) This invention relates to electrical toggleswitches of the type having a movable contactor mounted for tilting orrocking movement between various switching positions.

One object of the invention is to provide such a toggle switch having animproved driving connection between the manual operating member and thetilting contactor which requires reduced operating force and operateswith decreased friction and attendant reduction in wear.

Another object is to provide in such a toggle switch an operatingmechanism of simplified construction which can be fabricatedeconomically and is particularly suited for easy and rapid assembly.

Other objects will be in part obvious, and in part pointed out more indetail hereinafter.

The invention accordingly consists in the features of construction,combination of elements and arrangement ofparts which will beexemplified in the construction hereafter set fortuh and the scope ofthe application of which will be indicated in the appended claims.

In the drawing:

Figure 1 is a longitudinal sectional View of an assembled toggle switchconstructed in accordance with the present invention;

Figure 2 is a transverse sectional view of the toggle switch of Figure 1Figure 3 is an enlarged perspective view of the movable contactorelement of the switch shown in Figure 1; and

Figure 4 is an exploded perspective view of the contactor-operatingmechanism of the switch.

Referring to the drawing, and particularly Figure l, a toggle switchconstructed in accordance with the invention includes an insulatinghousing having a base 2 of molded plastic or the like, and a separatecover 4 of similar material which is fastened to the base by a clamp 6.The clamp has a central web 8 which seats in a recess in the top of thecover and has depending arms 1t) which resiliently engage the undersidesof projecting bosses 12 on the base so as to hold the cover and basesecurely together. Mounted on the upper surface of the base at one endthereof is an electrical terminal 14, one end of which projects from thehousing and carries a binding screw 16, and the other end of whichcarries a switch contact 18. Secured at the other end of the base isanother terminal member 20 which carries a binding screw 22 and has anupwardly struck portion forming a stop 24. Centrally disposed on thebase is a channel-shaped support 26 having upsanding transversely spacedsides provided with rectangular notches 28 at their upper ends. Whilethe channel-shaped support shown in the drawing is integral with theterminal member 20, the switch thus being arranged for single-throwoperation, it will be understood by those skilled in the art that thesupport may be electrically separated from the terminal member 20 and asecond switch contact provided on the terminal member for double-throwoperation of the switch.

nited States Patent y 2,780,691 iatented Feb. 5, 1957 ice , Thecontactor 30 is of sheet metal construction and includes a generallyelongate body 32 having reinforcing side flanges 34 provided withcentrally located outward- 'ly bent wings or trunnions 36 which cradlethe contactor in the notches 28 of the support for tilting movementabout a transverse axis. Each trunnion is formed with two inclined iiatsintersecting in a shallow V-shape, the apices of the Vs beingtransversely aligned and engaging the bottoms of the notches with linecontact in the manner of a knife edge so as to afford the contactor twopositions of stability in the support and permit the contactor to betilted abruptly from one position to the other. As will be understood,the trunnions may be provided with a third at stabilizing the contactorat an intermediate position for three-position operation of the switch.On one end of the contactor is a contact member 40 which in one of thestable positions of the contactor engages the fixed contact 18. Theother end of the contactor engages stop 24 in the other stable positionof the contactor, and may of course be provided with a second contactmember when the switch is arranged for double-throw or three-positionoperation. The contactor body 32 has a slight hump midway between itsends and is formed with longitudinally extending spaced shoulders 42between which is defined a longitudinally extending groove or track 44.

The top of the cover has a central opening in registry with which ismounted an upstanding sleeve or bushing 50 carried by the clamp 6. Thesleeve is threaded on its outer surface to permit convenient attachmentof the switch in an opening in a panel or the like, as by means of nuts52. Extending through the bushing is an operating lever 54 having alongitudinal bore 56 opening opposite the contactor, and having asomewhat enlarged spherical portion intermediate its ends forming athickened wall section through which extends a transverse pivot pin 60on which the operating lever is mounted for pivotal movement. The pivotpin is disposed parallel to the axis of movement of the tiltingcontactor 30 and is secured at its ends in the sleeve, as by staking.Slidably mounted in the bore 56 of the operating lever is a spring guideor casing consisting of a pair of transversely spaced longitudinallyextending sheet metal arms 62 having opposed parti-cylindrical surfaces64 provided with opposed longitudinal slots 66 through which the pivotpin extends. At their inner ends the arms have somewhat rounded portions68 which curve toward each other and partially close the space betweenthe arms. The outer ends of the arms project from the end of the boreopposite contactor Sti and are connected by a pin or stud 76 disposedwith its axis parallel to the axis of movement of the contactor. At theouter ends of the parti-cylindrical surfaces the arms are formed withopposed transverse shoulders 72 facing into the bore. A coil compressionspring 74 is disposed betwen the parti-cylindrical surfaces, andconfined at one end by the shoulders 72 and at the other end by thepivot pin 60 so as to urge the spring guide in a direction outwardly ofthe bore 56 and toward the contactor. The free length of the spring 74is such that the pivot pin 6d may be freely inserted through the slotsat their inner ends without compressing the spring.

forded by slots 66. The pressure of the wheel againstV the contactorproduced by the compression spring 74 keeps the contactor stationaryuntil the operating lever reaches dead center, and then as the wheelrolls over the crest of the hump on the contactor, the spring togglesthe contactor abruptly to its next switching position, therebyminimizing arcing.

AA switch constructed in accordance with the invention has manyadvantages. From an operationai standpoint, the rolling engagement ofthe wheel 76 with the contacter permits the switch to be actuated withreduced friction or wear on the operating parts, and with the exerciseof a minimum operating force. Moreover, with the arrangement describedthe spring guide may extend upwardly into the operating lever wellbeyond the pivot pin, the substantial length thereby afforded thelspring guide providing a long bearing surface having a minimum ofsliding friction and insuring against binding or sticking of the springguide, even after protracted use of the switch. Furthermore, theengagement of the pivot pin o@ with the sides of the slots 66 preventstwisting of the upper end of the spring guide, while the compiementarygroove i4 in the contactor assists in maintaining the wheel 7o in properalignment longitudinally of the contactor and prevents twisting of thewheel, thus minimizing friction and wear of the operating parts.

The switch also has several advantages from the standpoint of ease ofassembly. The assembly may be conveniently accomplished by assemblingthe parts carried by the cover, separately assembling the parts carriedby the base, and then joining the cover and base sections together. Thisprocedure is facilitated by the fact that the two arms 62, the spring74, the rotatable wheel 76, and the stud 70 can be conveniently puttogether as a subassembly, and when once joined by the stud, the armswill provide a. cage for the spring and prevent it from falling out orbecoming displaced during subsequent stages of the switch assembly.Since the pivot pin 69 may be freely accommodated at the inner ends ofthe slots 66 without placing the spring under compression, thissub-assembiy may then be inserted in the operating lever bore 56 and theoperating lever mounted in the sleeve Sti and secured by the pivot pin6i) without the inconvenience of compressing the spring. Moreover, whenthe pivot pin o@ is once inserted through the operating lever and theslots 6o in the spring gui-de and secured to the sleeve, it therebyserves to secure the spring guide within the operating lever andprevents it from inadvertently falling out when the assembled coversection is placed on top of the rest of the switch. lt will thus beapparent that the assembly of a switch is substantially simplilied andmay be accomplished with attendant savings in time and expense and withreduced fatigue of personnel.

As many changes could be made in the above construction and manyapparently widely different embodiments of this invention could be madewithout departing irom the scope thereof, it is intended that all mattercontained in the above description or shown in the accompanying drawingsshall be interpreted as illustrative and not in a limiting sense.

lt is also to be understood that the language used in the followingclaims is intended to cover all of the generic and specific features ofthe invention herein described and all statements of the scope of theinvention which, as a matter of language, might be said to falltherebetween.

I claim:

l. in an 'electric switch having a housing, a contacter supported in thehousing tor rocking movement between a plurality of switching positions,and a lever for operating the contacter mounted on the housing forpivoting movement about an axis parallel to the axis of movement of thecontactor, said lever having a longitudinal bore facing the contactor, ahollow tubular casing longitudinally slidable in said bore, a wheelrotatably mounted on the outer end of said casing for engaging thecontactor, a track in the contacter perpendicular to the axis 4 .ofmovement thereof for receiving said wheel, a longitudinal coilcompression spring urging said casing in one direction to move saidwheel into engagement with said track, and means extending into the boreof the lever engageable with the casing to limit movement of the casingrelative to the lever in said `one direction.

2. in an electric switch having a housing, a contactor supported in thehousing for rocking movement between a plurality of switching positions,and a lever for operating the contacter mounted on the housing forpivoting movement about an axis parallel to the axis of movement of thecontactor, said lever having a longitudinal bore opening opposite saidcontactor, a spring guide slidable in said bore having transverselyspaced longitudinal sides provided with opposed longitudinal slots, atransverse pin in said lever extending across Said bore through saidslots, a longitudinal coil compression spring disposed between the sidesof the spring guide and engageable at one end with said transverse pinand at the other end with a portion of said spring guide for urging saidspring guide outwardly of said bore, and a bearing member on the outerend of said spring guide engageable with the contactor.

3. In an electric switch, a housing having a support, a contactormounted on the support for rocking movement between a plurality ofswitching positions, a pivot pin mounted on the Jhousing spaced from theconta-:tor and parallel to the axis of movement of the contactor, anoperating lever pivotally mounted on the pivot pin and having alongitudinal bore traversed by said pivot pin and opening opposite saidcontactor, a spring guide slidable in said bore having transverselyspaced side walls provided with opposed longitudinal slots through whichsaid pivot pin extends, a longitudinal coil compression spring disposedbetween said side walls and engageable at one end with said pivot pinand at the other end with a portion of said spring guide for urging saidspring guide outwardly of said bore, and a bearing member on the outerend of said spring guide engageable with the contactor.

4. in an electric switch having a housing provided with a support, acontactor mounted on the support for rocking movement between aplurality of switching positions, and an operating lever mounted on thehousing for pivoting movement about an axis parallel to the axis ofmovement of the contactor, said lever having a longitudinal bore openingopposite said contactor, a spring guide slidable in said bore havingtransversely spaced longitudinal sides provided with opposedlongitudinal slots, a transverse pin in said lever extending across saidbore through said slots, a longitudinal coil compression spring disposedbetween the sides of the spring guide and engageable at one end withsaid transverse pin and at the other end with a portion of said springguide for urging said spring guide outwardly of said bore, and arotatable wheel on the outer end of said spring guide engageable withsaid contactor,

5. in an electric switch, a housing having a support, a contactermounted on the support for rocking movement between a plurality ofswitching positions, a pivot pin mounted on the housing spaced from thecontacter and parallel to the axis of movement of the contactor, anoperating lever pivotally mounted on the pivot pin and having alongitudinal bore traversed by said pivot pin and opening opposite saidcontactor, a spring guide slidable in said bore having transverselyspaced side walls provided with opposed longitudinal slots through whichsaid pivot pin extends, a longitudinal coil compression spring disposedbetween said side walls and engageable at one end with said pivot pinand at the other end with a portion of said spring guide for urging saidspring guide outwardly of said bore, a rotatable wheel on the outer endof said spring guide, and means forming a groove in the contacterkperpendicular to the axis of movement thereof for receiving said wheel.

6. In an electric switch having a housing provided with a support, acontacter mounted on the support for rocking movement between aplurality of switching positions, and an operating lever mounted on thehousing for pivoting movement about an axis spaced from the contactorand parallel to the axis of movement of the contactor, means forming alongitudinal bore in the operating lever, a spring guide slidablymounted in said longitudinal bore and extending from the end thereof,transversely spaced opposed parti-cylindrical surfaces on said springguide having opposed longitudinal slots, a transverse pin in said leverextending across said bore through said slots, inwardly facingtransverse shoulders on t-he spring guide spaced from said openings, acoil compression spring disposed between said parti-cylindrical surfacesand engageable at one end with said transverse pin and at the other endwith said shoulders for urging said arms outwardly of said bore, and arotatable wheel on the outer end of the spring guide engageable with thecontactor,

7. In an electric switch, a housing, a contactor supported in thehousing for tilting movement between a plurality of switching positions,means forming an elongate groove in said contactor perpendicular to thetilt axis thereof, a pivot pin mounted on the housing spaced from thecontacter and parallel to the axis of movement of the contactor, anoperating lever pivotally mounted on said pin, said operating leverhaving a longitudinal bore opening opposite said contactor and traversedby said pivot pin, a pair of arms slidably mounted in said longitudinalbore and extending from the end thereof, opposed parti-cylindricalsurfaces on said arms having longitudinal slots through which said pivotpin extends, transverse shoulders on said arms at the outer ends of saidparti-cylindrical surfaces and facing into said bore, a coil compressionspring disposed between said particylindrical surfaces and engageable atlone end with said pivot pin and at the other end Wit-h said shouldersfor urging said arms outwardly of said bore, a stud parallel to saidpivot pin extending between the outer ends of said arms, and a rotatablecam wheel on the stud in rolling engagement with the bottom of saidgroove in the contacter.

Krieger Ian. 14, 1936 Krieger Dec. 23, 1941

